Diamond



FIG. 1 is a perspective view of a diamond showing my new design;

FIG. 2 is a front view of the diamond of FIG. 1, the left side, right side and rear views being a mirror image thereof;

FIG. 3 is a top view of the diamond of FIG. 1; and,

FIG. 4 is a bottom view of the diamond of FIG. 1. 

The ornamental design for a diamond, as shown and described. 